--- /dev/null
+/*
+ * Copyright (c) 2011 The Chromium OS Authors.
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+#ifndef _UART_SPI_SWITCH_H
+#define _UART_SPI_SWITCH_H
+
+#if defined(CONFIG_SPI_UART_SWITCH)
+/*
+ * Signal that we are about to use the UART. This unfortunate hack is
+ * required by Seaboard, which cannot use its console and SPI at the same
+ * time! If the board file provides this, the board config will declare it.
+ * Let this be a lesson for others.
+ */
+void pinmux_select_uart(NS16550_t regs);
+
+/*
+ * Signal that we are about the use the SPI bus.
+ */
+void pinmux_select_spi(void);
+
+#else /* not CONFIG_SPI_UART_SWITCH */
+
+static inline void pinmux_select_uart(NS16550_t regs) {}
+static inline void pinmux_select_spi(void) {}
+
+#endif
+
+#endif
--- /dev/null
+# Copyright (c) 2011 The Chromium OS Authors.
+# See file CREDITS for list of people who contributed to this
+# project.
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License as
+# published by the Free Software Foundation; either version 2 of
+# the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+# MA 02111-1307 USA
+
+include $(TOPDIR)/config.mk
+
+ifneq ($(OBJTREE),$(SRCTREE))
+$(shell mkdir -p $(obj)board/$(VENDOR)/common)
+endif
+
+LIB = $(obj)lib$(VENDOR).o
+
+COBJS-y += board.o
+COBJS-$(CONFIG_SPI_UART_SWITCH) += uart-spi-switch.o
+
+COBJS := $(COBJS-y)
+SRCS := $(SOBJS:.o=.S) $(COBJS:.o=.c)
+OBJS := $(addprefix $(obj),$(COBJS))
+SOBJS := $(addprefix $(obj),$(SOBJS))
+
+all: $(LIB)
+
+$(LIB): $(obj).depend $(OBJS) $(SOBJS)
+ $(call cmd_link_o_target, $(OBJS) $(SOBJS))
+
+#########################################################################
+# This is for $(obj).depend target
+include $(SRCTREE)/rules.mk
+
+sinclude $(obj).depend
+
+#########################################################################
--- /dev/null
+/*
+ * Copyright (c) 2011 The Chromium OS Authors.
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+#include <common.h>
+#include <ns16550.h>
+#include <asm/gpio.h>
+#include <asm/arch/pinmux.h>
+#include <asm/arch/uart-spi-switch.h>
+#include <asm/arch/tegra2.h>
+#include <asm/arch/tegra2_spi.h>
+
+
+/* position of the UART/SPI select switch */
+enum spi_uart_switch {
+ SWITCH_UNKNOWN,
+ SWITCH_SPI,
+ SWITCH_UART,
+ SWITCH_BOTH
+};
+
+/* Information about the spi/uart switch */
+struct spi_uart {
+ int gpio; /* GPIO to control switch */
+ NS16550_t regs; /* Address of UART affected */
+ u32 port; /* Port number of UART affected */
+};
+
+static struct spi_uart local;
+static enum spi_uart_switch switch_pos; /* Current switch position */
+
+
+static void get_config(struct spi_uart *config)
+{
+#if defined CONFIG_SPI_CORRUPTS_UART
+ config->gpio = CONFIG_UART_DISABLE_GPIO;
+ config->regs = (NS16550_t)CONFIG_SPI_CORRUPTS_UART;
+ config->port = CONFIG_SPI_CORRUPTS_UART_NR;
+#else
+ config->gpio = -1;
+#endif
+}
+
+/*
+ * Init the UART / SPI switch. This can be called before relocation so we must
+ * not access BSS.
+ */
+void gpio_early_init_uart(void)
+{
+ struct spi_uart config;
+
+ get_config(&config);
+ if (config.gpio != -1) {
+ /* Cannot provide a label prior to relocation */
+ gpio_request(config.gpio, NULL);
+ gpio_direction_output(config.gpio, 0);
+ }
+}
+
+/*
+ * Configure the UART / SPI switch.
+ */
+void gpio_config_uart(void)
+{
+ get_config(&local);
+ if (local.gpio != -1) {
+ gpio_direction_output(local.gpio, 0);
+ switch_pos = SWITCH_UART;
+ } else {
+ /*
+ * If we're here we don't have a SPI switch; go ahead and
+ * enable the SPI now. We didn't in spi_init() so we wouldn't
+ * kill the UART.
+ */
+ pinmux_set_func(PINGRP_GMC, PMUX_FUNC_SFLASH);
+ switch_pos = SWITCH_BOTH;
+ }
+}
+
+static void spi_uart_switch(struct spi_uart *config,
+ enum spi_uart_switch new_pos)
+{
+ if (switch_pos == SWITCH_BOTH || new_pos == switch_pos)
+ return;
+
+ /* if the UART was selected, allow it to drain */
+ if (switch_pos == SWITCH_UART)
+ NS16550_drain(config->regs, config->port);
+
+ /* We need to dynamically change the pinmux, shared w/UART RXD/CTS */
+ pinmux_set_func(PINGRP_GMC, new_pos == SWITCH_SPI ?
+ PMUX_FUNC_SFLASH : PMUX_FUNC_UARTD);
+
+ /*
+ * On Seaboard, MOSI/MISO are shared w/UART.
+ * Use GPIO I3 (UART_DISABLE) to tristate UART during SPI activity.
+ * Enable UART later (cs_deactivate) so we can use it for U-Boot comms.
+ */
+ gpio_direction_output(config->gpio, new_pos == SWITCH_SPI);
+ switch_pos = new_pos;
+
+ /* if the SPI was selected, clear any junk bytes in the UART */
+ if (switch_pos == SWITCH_UART) {
+ /* TODO: What if it is part-way through clocking in junk? */
+ udelay(100);
+ NS16550_clear(config->regs, config->port);
+ }
+}
+
+void pinmux_select_uart(NS16550_t regs)
+{
+ /* Also prevents calling spi_uart_switch() before relocation */
+ if (regs == local.regs)
+ spi_uart_switch(&local, SWITCH_UART);
+}
+
+void pinmux_select_spi(void)
+{
+ spi_uart_switch(&local, SWITCH_SPI);
+}
projects / u-boot / commitdiff